v0.1.0 — Functional MVP

Functional MVP — Payment Gateway

Functional MVP implementation of the payment gateway service.

Features

• PAYGATE-1 — Implementation plan, OpenAPI specs, and C4 diagrams
• PAYGATE-2 — Characterization tests for GET /payment/{id}
• PAYGATE-3 — OpenAPI code generation for server interface and bank client
• PAYGATE-4 — Replace hand-written DTOs with generated models
• PAYGATE-5 — Domain model, entity, MapStruct mappers, and CQRS use cases
• PAYGATE-6 — Bank simulator integration with POST /payment
• PAYGATE-7 — PCI DSS log masking for PAN and CVV
• PAYGATE-8 — Externalize test fixtures to JSON files
• PAYGATE-9 — Externalize bank config with @ConfigurationProperties
• PAYGATE-10 — Validation edge-case tests for payment processing
• PAYGATE-11 — Catch-all exception handler to prevent stack trace leaks
• PAYGATE-12 — README rewrite and centralized dependency versions

Highlights

• POST /payment and GET /payment/{id} endpoints
• OpenAPI-generated server interfaces and bank client
• Request validation with descriptive error responses
• In-memory payment storage
• Configurable bank simulator connection (URL, timeouts)
• PCI-compliant log masking
• Swagger UI at /swagger-ui/index.html